Asking here because the same question on other forums/sections got conflicting answers, all seeming to be speculation.

Is it possible to run a larger diameter tire in the rear than the front, without triggering ABS/Traction Control or anything else bad?? Say an inch larger? The car is a 2104 GT.

Would appreciate hearing from someone who has tried this (or seen it first hand) on a GT, for a definitive answer. TIA!

 

Does the 2104 still look like the Fusion?

Btw, to answer your question, you'll need a tuner to adjust for taller rear tires, but yes, you can do it.

 

If you assume 27" diameter and an inch crease on the back you should expect ~3.7% change in the rolling radius of the tire. The ABS/TCS controller has a dead zone of ~5% or so, but that's cutting way into your safety margin for some driving situations. So you could potentially have some interventions, which is not good.

Tune would be the way to go.

 

Thanks Sirs. Having not done any tunes yet... what would be the easiest way to do this? Should I buy a tuner? And is it something I could do myself or could I buy tunes somewhere for the size difference?